Web users, including owners of websites, (referred to hereinafter as “site owners”) are interested in who is visiting a particular website and how often the particular website is visited. Such information is useful for generating advertisement revenue, determining what type of web content is attracting the most visitors, etc.
Site owners and researchers in general are also interested in web connectivity and how different sites on the World Wide Web are connected to each other. Beginning with a particular webpage, users may browse from the particular webpage to the webpages to which the particular webpage connects by following the “outlinks” on the particular webpage. However, users cannot browse in reverse, by finding who links (i.e., what webpages are linking) to the particular webpage and following the chain back.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.